Fins and Grins
by Anitoon3
Summary: Dean and Castiel in a mer-creature AU! Though not exactly Little Mermaid because there are lots of twists-which is more like I got a vague idea from the movie! There's romance, as well as fun and mischief underwater! Plus the whole fambam with the Winchester's and Novak's! Destiel :)


Hi there I'm Anitoon3 and I don't own Supernatural! That belongs to Eric Kripke!

So this is a Dean/Castiel mercreature (kinda like The Little Mermaid) AU so please enjoy!

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The dark waters swept gently from side to side, the wind rolled with it. The young merman and his younger brother were racing towards the kingdom after collecting some seashells. As Dean Winchester was weaving through large canyons, Sam took a short cut and was in front in no time, swimming faster to get to the finish line that they had settled on since the two begun the tradition years ago to race home. Sam looked behind him and was confused.

Dean was racing towards the kingdom when a muscled hand shot straight out, causing him to have the water knocked out of him as he slammed into it with such force. The merman laughed at Dean's plight. Trying to get away was futile when Dean got knocked into the canyon, being held there by the stronger merman. Dean yelled in pain but knew no one could hear him. Everyone was at the concert waiting for Sam and Dean to arrive while watching the entertainment. "So steroids, whatcha gonna do now?" Dean said as he felt his head spinning. The dude laughed "Oh wouldn't you like to know princess?" and full on smirked at Dean.

Sam felt terror at seeing the merman holding his older brother up against the wall, and then charged at the man, prepared to strike. Suddenly the force of the guy's strong punch as he turned around, resulted in Sam landing on the ocean floor. As Dean was struggling to go to his brother, the merman's weight was gone as a blur shot past.

Castiel Novak was minding his own business when he heard screams outside his own kingdom. After making sure that bag was tied tight, he set the fish on the floor near the gate before turning to help the ones that were in danger. As the commotion registered, he took off like a bullet.

At this moment Castiel was thankful for his larger-than-normal back fin and tail. One huge fin was in-between his shoulder blades traveling downward until it reached his lower back (though not connected to where his lower half started). Castiel's tail led to a slightly straighter fin, but was in no way lacking the size of the one on his back. Plus his whole anatomy was basically muscle anyways, though not too much muscle to where it was weird. Most of his life, Castiel was teased and the butt of jokes by his older brothers for having both so large. Now he couldn't be more grateful as it would help him if there were a fight.

After barreling in and flinging the merman a few feet away, Castiel glanced behind him to the other merman who rushed to the younger one, before returning his steely-nearly blackened-gaze to the one in front of him. "Yo man what's your problem?!" the guy said, making Castiel lung forward, all the while baring and snapping his sharp, elongated teeth. The beefy merman flinched and took off screaming. Castiel breathed a sigh of relief before retracting his teeth to a more manageable size, so as not to freak out the two mermen.

After checking that Sam was okay, Dean turned to thank his savior. Seeing dark brown (to the point it was almost black) wild sex-like hair, deep blue eyes, firm muscles, and strong dark blue (mixed with a bit of black to make it overall darker) fins. He then noticed the other parts of the dude's body-all shark. As soon as their eyes locked, both felt something strange-as if a bond drew them together. Castiel's only thought as he stared at the merman was _Beautiful_. Dean had dirty blonde hair, green eyes with flickers of yellow and light brown, and a forest green tail (with their tips flared out to a more wavy look).

Dean kept getting lost in those dark eyes. While they both drew closer, Sam thanked the stranger. "Thanks for saving us. I'm Sam Winchester and this is my brother Dean. What's your name?" As Castiel answered, Dean zoned out staring at luscious lips. Blinking at the fingers in front of his face, Dean looked at Castiel questioningly. The mershark chuckled slightly and repeated himself. Dean felt embarrassed when he squeaked that he was alright as a reply, but he couldn't help it! Castiel had a deep and sexy voice! It was doing things to him that thankfully no one would notice.

Sam noticed how Dean and Castiel were acting towards one another, an idea forming in his mind. "Hey Castiel would you like to come and see our concert?" To which Dean was anxious of the reply. Castiel nodded his head and said yes. He said that he would tell his father and brothers, then be out to go with them. Castiel dropped off his fish and went and asked his family, who said yes. Castiel said thanks and went out to meet Dean and Sam, and then they were off to the concert.

Swimming into Mer-Fishales at a somewhat hurried pace, though not so much that Castiel didn't take in his surroundings. There were tons of places to look at with apartments, markets, and few schools thrown in as well. The rocks and coral-like shapes were swirls of color that one couldn't help but admire. Most of his own kingdom's building had a dark blue color to them. Still, no one found it drab or boring even though to an outsider it would seem as much. Castiel liked the palace as well for it was a mixture of different types of darker blues.

As they swam to where the concert was happening Sam and Dean took the time to tell Castiel what they would be performing. "So when we get on stage, me and Sammy are gonna be doing different things. Sammy'll do his magic tricks, and I'll be singing." Not that these sounded weird, but Castiel was wondering what prompted the concert in the first place. He asked as much and Dean said that it was their mother's birthday and that their father wanted to something nice for her, while saving their sons for the last act.

As the three neared the balcony where the Winchester parents were, Castiel began to feel nervous. He supposed it showed on his face because Dean patted his shoulder. "Aw don't worry Cas. Our mom will love you and though dad seems like a hard ass, eventually he'll like you." As the merman grabbed his hand and led him forward, the mershark felt some nervousness ebb away from him.

Seeing Mary and John Winchester was different from hearing about them from his older brothers catching him up on how the peace treaty went since he missed it because he was off hunting. John was a big merman and very intimidating. His dark blue tail looked powerful with his muscles tense from seeing Castiel. It was understandable since the two kingdoms hardly interacted outside of those in politics.

Looking at the queen, Mary Winchester was a beauty to behold. A golden yellow tail that had the tips in a more wavy pattern that ended with them gently flowing, accented by blonde wavy hair-and looking into her eyes it was easy to tell where Dean got his eye color from. Though his was slightly darker. Seeing Sam move to hug his mother after Dean, Castiel could tell that Sam go the yellowness of his fin from his mother, while Dean got a blend of both his parent's combination to make a dark green. Dean's tip of his tail took after his mother's, both having wavy ends.

Staring at the small family, Castiel couldn't help but notice the differences in his own family. His father Chuck had a gray fin and gray eyes. Castiel's oldest brother Michael had a silver fin and hazel eyes, both of which he got from his mother, Becky. With Michael's good looks, many sharks in the kingdom wanted to mate with him. When Chuck got together with his second wife Naomi (after Becky left) their son Lucifer was born. With his dark purple fins and blue eyes, many sharks thought he was mysterious looking.

Gabriel was the brother who played lots of pranks on others, with no shame to show for it. Time and time again did Chuck have to bail him out trouble by paying for the damages that his son caused. Gabriel's mother became so fed up she left Gabriel, saying she couldn't handle him anymore. Anna was the only sibling who rebelled and went vegetarian, like her mother. Chuck was left once again and all because he wouldn't become stop eating meat.

Finally there was Castiel, the youngest of four siblings. No one knew why both his fin and tail were so large, so everyone just chalked it up as an anomaly. Besides the people who were shocked at the sight of him, there were also people who were afraid of Castiel. Being the third biggest species of shark - other than Chuck and Michael - in the royal family, people tended to believe that he would be demanding and cold like that of sharks in other kingdoms. Though that couldn't be further from the truth. All of Castiel's family had the mantra of not being vicious (and thus using the force of their power) unless they had too.

Though not his lineage or power could make Castiel intimidate John. Plus he just did not want to. John could clearly see that in him, for he shifted from cold and steely to curious and weary. "And who is this boys?" Hearing Dean tell what describe what Castiel did for them made a little warm bubble flutter in his stomach. Seeing Dean smile when he finished his story was the highlight of Castiel's day.

John stared at his oldest son and the mershark. "Thank you for saving my sons Castiel. If there is anything I could do for you please don't hesitate to ask." Castiel could hear the change in the man's voice after hearing of the days' events. Looking at Mary it was also apparent how it affected her. "Would you like to stay for the concert Castiel? It's my birthday today and my boys will be in it, so I'm sure that it will turn out great."

"My family says it's ok, so yes ma'am I will." Mary's face lit up with a radiant smile. "Fantastic! You shall be our guest of honor." Castiel felt a bit embarrassed "Really? Thank you." His attention was once again pulled towards Dean. The merman rested his hand on the mershark's shoulder and said "See ya Cas." then hurried off to the stage with his brother behind him. As the lights began to dim the king and queen sat down in their special seats with Castiel in the extra seat by Mary.

Mary looked over and saw Castiel looking with a little curiosity at Sam when he performed his juggling act and then a card trick. But when Dean came out and started singing it was like Castiel was enraptured. He simply could not take his eyes off of him. The young mershark felt eyes on him and turned his head to see the queen looking at him knowingly, a small smile on her face. "Castiel would you like to come to dinner with us tonight? I'm sure Dean would appreciate it." Blushing, he stuttered a yes in reply.

When the concert was over, Castiel went back with the Winchesters to their castle and into the dining room where he was in awe of the amount of food there. There was shrimp, tuna, halibut, crab, lobster, eel, crab cakes, and other assortments. It was rare that he got to eat a variety. Usually when he came back from a hunt, they usually ate one or two types of fish. Though what he did bring back, there was plenty of, so there was no need to worry about starvation.

Sitting next to Castiel was a joy to behold. Hearing him ask Sammy about his jokes when he didn't fully understand them, and answer his parent's questions to the fullest extent was interesting to watch. But when he started eating, Dean was in awe at how much the mershark packed away. He thought he himself ate a bunch but that was nothing in comparison. The young mershark scarfed the food, barely taking time to inhale and chew. It amazed Dean to watch Castiel.

Soon dinner was over and it was time that Castiel went home. Dean and Sam went with him as well, to be courteous. As the swam the 20 minute distance to the mershark's kingdom, jokes and stories were told to Castiel, with laughs and embarrassed grumbles from the brothers occasionally. They reached their destination and Sam was the first to speak. "Thank you so much for today Castiel. You're a nice guy." Then Castiel blinked in shock as Sam hugged him. He stiffened then patted Sam's back twice.

Dean's hug was different. It wasn't awkward at all as Dean put his arms around Castiel's neck and held him close. He smiled when Dean said "You really saved our tails back there. We would've been chum if it weren't for you. Plus you really hit it off with my parents! They seem to love you. So come back and visit soon m'kay Cas?" Touched that Dean gave him a nickname he nodded eagerly "Yes Dean I will see you again soon. Goodnight." Before going into the gate he heard the brothers say bye, and chuckled to himself. It had been a good decision indeed to help the Winchester brothers. Castiel could hardly wait to see Dean again.

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**Author's note**: Hey so hope you guys liked the first chapter!

Oh so when I was thinking of this, I thought that the kingdoms wouldn't be close to the surface at all because then humans might get them, and I didn't want that. I read somewhere that in The Little Mermaid, Atlantica was like close to the surface kind of and I was like 'what if people find them?'.

Oh and when I imagined the Castiel chasing off the bully, I pictured Scar snapping at Zazu in the Lion King near the beginning! And when I wrote Castiel thinking Dean was beautiful, I thought of O'Malley speaking about Duchess in Aristocats in the scene where Duchess sings in "Everybody Wants to be a Cat".

Ok so Dean and Sam, their parents, and Balthazar are merpeople, Cas is a Mako Shark (if you want, search Mako shark color an look at the 14th or so picture! That's kinda what I was aiming for when describing Cas' color - a bit more darker blue, though the color's still cool you know?), Gabriel is a Lemon Shark, Lucifer is a Bull Shark, and Anna is a Nurse Shark. Oh and Crowley and Bobby are crabs.

Also, even though sharks have sensitive eyesight the further down below they are, let's pretend that in this story, they don't. As well as the fact that they need to keep swimming or they'll die. I'm gonna have them rest and be still, and they won't drown or die.

I'll post the other couples at the beginning of the next chapter!


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